Structural Characteristics and Electrode Activities of Phosphorus Incorporated Tetrahedral Amorphous Carbon Films

Abstract

Studies on structural properties and electrochemical behaviors of conductive phosphorus incorporated tetrahedral amorphous carbon (ta-C:P) films deposited using filtered cathodic vacuum arc technique with PH₃ as the dopant source are presently reported. The structural characteristics of the films are characterized by X-ray photoelectron spectroscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The electrochemical reactivity of ta-C:P films are evaluated by cyclic voltammetry and differential pulse voltammetry. We find that phosphorus implantation enhances the clustering of sp² sites dispersed in sp³ skeleton, develops the densities of π and π * states and improves the electrical and electrochemical behaviors of the films. It has been established that the inorganic films with amorphous structure appear excellent electrical conductivity and electrochemical activity similar to boron-doped diamond or nitrogen-doped amorphous carbon electrodes. These characteristics demonstrate greatly potential application of ta-C:P films as electrode materials in terms of its large electrochemical potential window, low background current, and a considerable electrochemical activity towards ferricyanide reduction and metal ions analysis.

Keywords:

• Cyclic voltammetry
• filtered cathodic vacuum arc
• electrodes
• phosphorus incorporated tetrahedral amorphous carbon films